Internal combustion engine



July 25, 1933. M WOOLSQN 1,919,286

INTERNAL COMBUSTION ENGINE Filed July 22, 1930 agmpw Patented duly 25,1%33 ,uni'rsn STATES rarsnr orrica LIoNnL M. wo LSON, DECEASED, LATE ornnraorr, MICHIGAN, BY EMMA r. WOOLSON,

EXECUTRIX OF BLOOMFIELD VILLAGE, MICHIGAN, ASSIGNOR TO PACKARD MOTOR GABCOMPANY, OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN" INTERNALooMBus'rIoN ENGINE Application filed July 2%,

This invention relates to internal combustion engines, and particularlyto fuel injection mechanisms for engines of the Diesel type, in whichliquid fuel is injected under pressure into each engine cylinder at orto- 5 ward the end of the compression stroke of the associated piston. I

Generally, engines of the Diesel type are designed and intended to beoperated at substantially uniform speeds. In such instances the fuelinjection mechanism, which is actuated from some moving part of theengine, also operates at a uniform speed, with the result that uniformquantities of fuel are successively delivered to the engine cylinders inequal intervals of time. Where an engine of this type is designed andintended to operate at varying speeds, however, it is sometimes foundthat an engine-driven fuel injection mechanism will vary in theeffectiveness with which it performs its functions; that is, at lowspeeds for instance, the efiiciency of fuel injection falls considerablybelow the efficiency of the same mechanism at high speeds, the fuel notbeing so efficiently sprayed into the combustion spaoewhen theengine-driven fuel pump plunger ceases to move at a comparatively highvelocity. As the efficiency of the engine is, in large part, dependentupon liquid fuel andthe instantaneous and thorough admixture of theliquid fuel with the air under compression'in the cylinders, it is clearthat any decreased efiiciency of injection is highly undesirable. 35 Thepresent invention contemplates an improvement in an engine-drivenfuel'injection mechanism whereby the amount of fuel injected and thetime of injection remain constant regardless of the speed at which theengine is operating.

By means of the improved fuel injection mechanism hereinafter to befully described, it is possible to efficiently operate the engine notonly at maximum speed but also at much lower speed, as when starting .oridling. In accordance with the invention,

the fuel injection plunger or member, whatever its shape or design maybe, is actuated by means of a motor, such as a spnng motor,

instead of being positively operated by some the proper injection ofthe.

of the radial type or for usewith engines in 1930. Serial No. 469,391.

engine-driven part. This motor is intermittently loaded andintermittently released by engine-driven parts and in reality comprisesany simple means for translating a portion of the kinetic energy of theengine into potential energy, which potential energy is momentarilystored and finally released at the proper time by an engine-driven part.The liquid fuel plunger may be driven by any one of a number ofdifierent-kinds of motors, practically the only requirement which themotor mustfulfill being that it shall operate the fuel plunger at asubstantially uniform rate, when released. i In the accompanying drawingone embodiment of the invention is illustrated, but it will be,appreciated by those skilled in the art that the basic underlyingprinciple 'of' the invention is quite independent of this disclosure,which is set forth by way of ex ample only, andsthat many changes in thedesign and arrangement of the component elements of the invention may bemade without departure from the spirit and scope thereof.

In the drawing: v

Figure 1 is a fragmentary view, partly in section and, partly inelevation, of a portion of an internal combustion engine of which theimproved fuel injection, mechanism com prises a part; and

Figure 2 is a side elevation of a portion. of the mechanism disclosed inFigure 1.

It will be understood that'the improved fuel injection mechanism whichcomprises the subject matter of the invention is ap- Dwhether stationaryor of the portable type.

It may also be adapted for use with engines which the cylinders are inparallel relationship. In the present instance themechanism is disclosedas comprising a portion of a Diesel engine in which thecylinders areradially disposed, particularly designed for use as a power plant for anaeroplane, the innproved fuel injection mechanism being of greatusefulness when incorporated in an engine of this type. 1

One of the cylinders of the engine is indicated at 10 and the crankshaftat 11. The

one end of the rocker 17 and the lower end of which rests in a socket ina push rod operating lever 19, which lever is pivotally mounted on aboss or short shaft extending laterally from the casing member 12. Lever19 has rotatably mounted thereon a roller 21 which runs upon the outersurface of a cam ring 22 fixed on the crankshaft 11. Cam lobes 23 on camring 22 are positioned to successively engage roller 21, each therebyeffecting the lifting of lever 19 and push rod 18, thus opening thevalve. After the engaging cam 23 has passed roller 21, the push rodisallowed to descend, and the valve is closed.

A fuel injection nozzle is indicated at 25,

and a pump member for injecting fuel through this nozzle into thecombustion space within the cylinder is indicated generally at 26. Thispump comprises essentially a cen-- tral sleeve-like member 27 having anaxial cylindrical bore 28 which comprises the pump cylinder. The space28'is connected to nozzle by a conduit (not shown) so that fuel placedunder pressure by upward movement of the plunger 29 is conducteddirectly to the nozzle.

A non-return valve 30 permits upward flow of the liquid fuel butprevents return of the same due to any high pressure which may exist inthe cylinder. Surrounding member 27 is a barrel member 31, and mountedon member 31 is a. third member 32, members 31 and 32 enclosing betweenthem a space 33 which is in communication with a source of liquid fuelunder light pressure.

1 Members 27 and 31 are provided with registering ports providingconduits 34, by means of which fluid may flow from space 33 inwardlyinto pump chamber 28 when the upper end of plunger 29 has been withdrawnto a point below the level of-conduits 34. Uponvthe upwardstroke'of theplunger, a certain definite quantity of fuel is trapped in the pumpchamber 28 when the pump plunger has reached suchv position that theconduits 34 are closed, and, upon continued upward movement of theplunger, the entrapped fuel is placed under high compression, the checkvalve 30 is raised, and a quantity of fuel is injected into thecylinder.

It will be observed that the plunger 29 is an elon ated rod-like memberwhich extends general y parallel to the valve pusher rod 18.

Its. upper end has a close sliding fit with the wall of chamber 28, andits lower end slidably engages the wall of a cylindrical aperture whichextends through a plug 35. This plug is threaded into the lower end of alight tubular casing, or housing 36, the upper end of which ispreferably formed integral with member 31, and the lower end of whichfits closely llIltO a circular aperture formed 1' 1') the substantiallyhorizontally extending member 13 of the casing. Toward its upper end,plunger 29 is provided with an annular collar 37 which constitutes anabutment for one end of spring 38. Spring 38 is a coiled spring normallyunder compression, its lower end being seated upon the upper'surface ofplug 35. The lower end of the fuel injection plunger 29 is enlarged andprovided with two spaced annularfianges or collars 39 and '40,respectively. ,Collar 39 comprises a stop, limitingthe upward movementof the plunger by contacting with an adjustable stop member 39 which isthreaded upon an axial, externally threaded, downwardly projecting,spindlelike portion of plug 35. Upon the upper surface of the lowerterminal flange 40 of the plunger rests the ends of two-parallel rockerarms 41, mounted to rock upon a fixed spindle 42 projecting laterallyfrom the frame member 12, the opposite ends of rocking levers 41 restingupon the upper surface of a flange 18 fixed upon or formed integrallywith the push rod 18.

It will be obvious that upward movement of the push rod 18 will causedownward movement of plunger 29 and compression ofspring 38. In itsdownwardmovement the lower surface of the enlargement 40 of the plunger,which is rounded for the purpose, thrusts aside the upper end of apivoted sear or locking member 43, and, after the plunger has descendeda predetermined distance, the laterally extending catch portion 44 ofthis sear snaps over the'u'pper edge of enlargement 40 and engages theupper surface-thereof thus locking the plunger 29 in the loweredposition to which it has ji1st been moved.

Sear 43 is mounted to rock upon boss 20 and is normally urged in plungerlocking direction by means of a spring 45, one,end

of which engages the sear and the other end of which bears against a.pin 46 fixed in frame member 12. The lower tip end 47 of thesear restsupon the upper surface of cam ring 22, driven from the crankshaft, andis in position to be successively engaged by a series of cams 48thereon. Engagement of a cam 48 with end 47 of scar 43 results inanticlockwise movement of the sear and disengagement of the sear andmember 40, thus effecting the release of the plunger, whereupon it isimmediately driven upward in fuel feeding direction by the spring 38. l

The cams upon the camring 22 are so a'rranged that the spring 38 isplaced under stress at any suitable time prior tothe instant when thefuel is to be injected, and the sear is released at the exact instantwhen it is desired that the fuel shall be introduced into the cylinder.It is obvious that the time of movement of plunger 29 on its fuelinjection stroke is dependent entirely upon the action of spring 38 andentirely independent of the speed of rotation of the crankshaft. As aresult, ideal conditions of fuel injection are realized, whether theengine itself is operat-ingat high speed and under load or whether it isbeing started or run'idly at low by any suitable means, therefore,effects adjustment of stop 39* axially of the plunger .29, and hence thestroke of the plunger may be varied at will to modify, as desired, thequantity of fuel injected into the cylinder at each plunger stroke.

Instead of the spring disclosed as a suitable means for actuating theplunger in its fuel injection direction, any other suitable type ofmotormay be employed, The function of the motor is to store'momentarilya portion of the kinetic energy of? motion of some moving portion of theengine, that is, to translate this kinetic energy into potential energy,which energy is released at the proper instant, preferably by some othermotor-driven part. Itwillbereadilyapparentthat,instead of the springdisclosed by way of example,

other types of motors may be chosen, and it will also be obviousthat'the invention is in nowise limited to any particular mechanism.

for loading or releasing the motor. Adaptation of the invention toengines of different I types will require considerable modification ofits component elements, but many modi-- fications maybe made withoutdeparturefrom the spirit and scope of the appended claims.

Having thus described the inve'ntiom what is claimed as new and desiredto be secured by Letters Patent is 1. In an mternal combustion engine,in

combination, a fuel injection member, a motor 1n which energy may bestored, means actuated by a moving part of the engine for impartingenergy to the motor, means for.

maintaining said motor in energy storing condition, which means isadapted to be operated by an engine-driven part to release said motorirrespective of the condition of theenergy imparting means, and meansoper-' actuated by energy atively connecting said motor and fuel injection member whereby said member is operated when the motor is released.

2. In an internal combustion engine, in combination, a fuel injectionmember, a

motor operatively connected thereto for con-- tinuously urging the samein fuel feeding direction, an ntermittently operated englne part forloading the motor, and separate means whereby the motor maybe releasedby a moving part of the engine, and the fuel injection member therebyoperated.

3. In an internal combustion engine, in

combination, a fuel injection member, means connected to said member fortranslating a portion of the kinetic energy of a moving part of theengine into potential energy, second means. for holding said first meansstationary andpreventing release of said potential energy, and-mechanism actuated by a moving part of the engine for effecting thetimed actuation of said second means and the actuation of said member bythe potential energy stored in said first mentioned means.

4. The combination with the cylinder of an internal combustion engine ofmeans for intermittently injecting identical quantities of fuel thereinin equal intervals of time, said means comprising a plunger, resilientmeans associated with the plunger and adapted to, move the same in fuelfeeding direction, means for stressing the resilient member, a

tionary and in stressed condition, and means for actuating said deviceand effecting the release of saidresilient member.

- 5. In an internal combustion engine, in

device for holding the resilient member stacombinatiomia fuel injectionmember, a

motor operatively connected thereto for always urging the samein fuelfeeding direct1on;,a motor loading member movably supportedon the frame,and mechanismasso ciated with the motor and engine whereby said motorloading member is intermittently derived from, the engine to loadthe-motor, tion, and released by an engine-driven part.

6. In an internal combustion engine, in combination, a fuel injectionmember, and

stationary means associated-with said mem- 1 her forabsorbing energyfrom a moving part of the engine, storing the same momentarily andreleasing such energy to effect actuation of the member. in fuel feedingdirection. v "7. The combination with the fuel injection member of aninternal combustion engine of a motor mounted on the engine frame foractuating the same in fuel feeding direction, and independent engineactuated means for loading and effecting the release of said motor. p

8. In an internal combustion engine, in

locked inlloaded condicombination, a fuel injection plunger, a

spring for continuously urging the ,said member in fuel in ectiondirection, engine ing devices.

10. In an internal combustion engine, in combination, a crankshaft, acylinder disposed radially thereto, a valve controlled port in thecylinder wall, a radially disposed push rod connected to said valve, acam ring mounted on the crankshaft for actuating said push rod, a fuelinjection plunger, a spring for urging said plunger in fuel deliverydirection, a connection between the push rod and plunger whereby thelatter is retracted when the former is moved in one direction thusstressing the spring, a device for locking the plunger in retractedposition with the spring under stress, and. engine op- I erated meansfor actuating said locking device and effecting the-release of saidplunger, whereupon the plunger is moved on its fuel injection stroke bysaid spring.

11. The combination set forth in claim 10 in which the connectionbetween the push rod and plunger comprises a lever mounted to rock about'a fixed axis, the ends of said lever engaging the push rod and plunger,respectively.

12. The combination set forth in claim 10 in which the push rod andspring releasing mechanisms are both actuated by a common engine part,which is driven by the crankshaft.

EMMA F. WOOLSON, Ewecutriw of the Estate of Lionel M. W 00lson,Deceased.

